Effects of sleep and circadian rhythms on epilepsy

Abstract

Epilepsy and sleep have many interactions. There are multiple epilepsy syndromes that present with either exclusively or predominantly nocturnal seizures. Particularly interesting is the association of seizure propensity and sleep stage, and the fact that seizures are very rare in REM sleep. Furthermore, sleep loss, and sleep disorders may impact epilepsy. Particularly robust is the effect of obstructive sleep apnea, a fairly common sleep disorder. Last but not least, circadian rhythms may have an interesting effect on seizure propensity. Studies in children and in adults indicate that the time when seizures occur may not be random and depends on the epileptogenic region, with frontal lobe seizures being more frequently occurring from sleep and during the early morning hours, and temporal lobe seizures occurring more frequently from wakefulness and in the mid to late afternoon.